The Naabtal 50 Ultralauf is a small German ultra and marathon-style race held near Duggendorf in the Upper Palatinate, originating from organizer Andy Brey's home region. It is a loop race, not point-to-point. Runners may complete the same circuit for up to six hours; the shorter ultra option covers 43.2 km. The event is intentionally small, with its field expanding from around thirty to forty-five runners when demand exceeded available spots.
The race has a very handmade character. Brey, a triathlete and runner, manages it with a basic setup described as a carport, two buckets, and green paint. Participants receive ample cake, tea, and coffee, and some runners contribute baked goods. One iteration used a 2.272 km loop repeated 19 times for the 43.2 km distance, presenting a mental as well as physical challenge. The participants are largely familiar with the local ultra scene, and the race has also been conducted as a private group run.